This invention relates to the field of jet drop recording and more particularly to binarily switched array type recorders of the kind generally shown in Taylor et al. U.S. Pat. No. RE 28,219. Such array recorders generate a plurality of rows of drop streams which are individually switched from "print" to "catch" trajectories. Solid coverage of a print receiving member is achieved by staggering of the rows of jets, and registration of the image is achieved by row-to-row switching delays, all as described in detail in the Taylor et al. patent.
One of the major problems in printing with recording systems as taught by Taylor et al. is in accurate spacing and alignment of the various heads or bars which generate the individual rows of drop streams. One solution to this problem is taught by Cassill U.S. Pat. No. 3,580,515, but setting up and operating a large number of bars as taught by Cassill is quite tedious and expensive. Moreover, the relatively large separation between the bars requires fairly long switching delays, which greatly complicates the data handling problem.
Another solution to the row spacing and alignment problem is taught by Mathis U.S. Pat. No. 3,701,998 wherein the rows of drop streams are generated and switched by a single head. The Mathis arrangement provides highly accurate row spacing and alignment at relatively little cost, but provision is made for only two rows of jets. Even with relatively sophisticated manufacturing techniques it is difficult to obtain close spacing between the jets within one of the rows, and hence the Mathis recorder is somewhat limited as to the resolution which may be obtained in the recorded image.